Lacing shoes are still commonly spread in comparison to shoes without laces such as the so-called slip-on shoes or in comparison to shoes with a velcro fastener. Usually shoelaces are tied up to bowknots after putting on the shoes to protect it from self opening.
To avoid the necessity of binding bowknots, a clamping gadget for shoelaces is described in DE 891 065, allowing to pull the shoelaces to any tightness and clamping it. An improper loop, that opens when putting off the shoes and a resulting knot is avoided by means of the previously mentioned clamping gadget. This clamping mechanism described in DE 891 065 basically consists of a wedge shaped casing and a corresponding wedge. In closed position the wedge presses the shoelace ends against the casing side and locks the shoelaces by clamping.
To attain an open position of the clamping gadget, i.e. a position, where the shoelaces can be moved back and forth in the clamping mechanism, the wedge has to be set to the open position manually. To avoid clamping the shoelace in a closed position again, the wedge must be continuously held by hand in an open position, but this means, that one user's hand is needed to keep the wedge in open position, as long as the shoelace has to be moved. For this reason, the user has only one hand free for other tasks, e.g. tightening the laces.
The problem, that in the open position of the clamping gadget always one hand has to be free for holding the open position of the wedge or a corresponding lever, is solved by the design in accordance with U.S. Pat. No. 6,339,867 B1. From this previously mentioned document a clamping gadget consists of a hollow body according to U.S. Pat. No. 6,339,867 B1 containing two clamping cams as well as a cogged wheel to lock the shoelaces. The hollow body is connected with a spring pressing the cogged wheel in the hollow body in a closed position and supporting the clamping of the shoelaces between wheel and cams. The hollow body can be engaged in open position and the release of the engagement is effected by pulling the shoelace in its pulling direction against the force of a second spring. A certain force has to be exceeded to attain that, determined by the previously mentioned spring.
The force needed to set the clamping gadget in accordance with U.S. Pat. No. 6,339,867 from its open position to a closed position is increased by the spring force. Furthermore, the clamping mechanism shows a complex design in accordance with the previously mentioned document. Additionally, the tightening degree of the shoelaces is fixed by the above described spring, so it is not possible to tie the shoe relatively loose or relatively tight in adaptation to the need or application field. The user is forced to a certain tightening by the previously mentioned design, that is not individually adjustable and decreases unwanted in the course of time by the weakening spring force.
The present invention is intended to show a clamping mechanism for shoelaces as well as the corresponding shoe, designed as simple as possible and allowing an engagement in open position with a minimum of constructive complexity.
So it is an essential feature of the invention, that the locking in open position of the clamping gadget can be released by a movement of the locked shoelace in one direction of the pulling direction of the shoelace. This ensures a simple design as well as an engagement release with low effort. The release of the locking against the force of an elastic element is not necessary.
By preference, a gadget in accordance with the invention consists of a base part holding the shoelace, a sliding part attached to the base part and an elastic element effective between base part and slider, against its force the clamping mechanism can be set into the open position. A gadget designed this way consists of just three components emphasizing the low constructive complexity also resulting in low production costs.
In a preferred design version base and slider are shaped shell-like and face each other in a way, that they form a holding space for the shoelaces. A shell-shaped design of base and slider ensures a simple production on the one hand, and material savings on the other hand, as such a gadget doesn't need a separate casing. The casing of conventional designs is delimited by base and slider in accordance with the invention.
By preference the shoelace is clampable between base and slider. This design version also emphasizes the low constructive complexity, especially in comparison with the state of technology. Complicated mechanisms such as cogged wheels or the like are not necessary to clamp the shoelace.
Preferably the sides of base and/or slider facing the shoelace are cogged to ensure a secure clamping of the shoelace.
The elastic element is preferably a spring mounted between base and slider, especially a helical compression spring, as it is low cost and ensures a reliable effect.
In a preferred design version the base includes a baseplate for the attachment to the tongue of a shoe or to the rim of a rucksack opening or the like container. By attachment of the clamping gadget locking the open position is solved even more simply and user-friendly.
By preference, the slider is shaped like a trough or lever to set the clamping mechanism from the closed position to its open position. A trough form has the advantage, that it can be adapted to the form of a finger and the mechanism can be handled for example with a thumb. Additionally, no protruding parts are present in the gadget. A lever shaped otherwise, for example in the form of a projecting lever, allows an easy grasping of the lever, for example for users with low finger power.
The slider preferably includes a protrusion to engage the slider at the base in open position, where the slider is fixed in its engaged position against the effect of the elastic element mounted between slider and base. By preference, the projecting notch can be moved past an edge of the base in a way, that the slider can be swiveled into the motion path of the shoelaces. These constructive measures ensure a secure engagement of the slider with a minimum constructive complexity.
Alternatively, the notched protrusion may also be located at the base and the corresponding notch at the slider.
The purpose of the present invention relating to the shoe is solved by providing a shoe with a clamping gadget solved according to one of the previously described design versions. The advantages of such a shoe are analogous to the previously described design versions of the clamping gadget.
By preference, the shoelace forms a loop at one end of the lever to allow a handling with one hand or a single finger. So the operation of the shoe can be performed with one hand. Setting the clamping mechanism from the closed position to the open position as well as a following tightening or loosening and setting the clamping mechanism to the closed position again can be performed with one hand or, if the baseplate of the clamping gadget is attached to a shoe tongue or the like, it can be handled with a single finger.
For a better grasping of the shoelace or to ensure, that the shoelace doesn't cut into the finger at a high pulling force, the shoelace loop can be equipped with a lever, for example in a husk shape.
By preference, the shoelace ends or the shoelace loop and/or eventually the lever of the shoelace are connected by an elastic band, so that the shoelace and eventually its lever is pulled towards the shoe. This ensures, that the shoelace ends or the shoelace loop and/or the lever of the shoelace lies flat on the shoe to avoid the danger of stumbling. Additionally, the lever is always in a reachable position.
The elastic band is preferably mounted on the shoe in a band guide or in band liners, also including the guides for the shoelaces. This multi-functionality means a low material expense and provides an attractive shoe design.
In a preferable design version the elastic band is lined by a guideway mounted to the shoe, especially around the shaft of the shoe, i.e. the elastic band is held in position by the guideway to prevent it from slipping. This ensures the desired attachment of the lace at the shoe.
In explanation of the principle of the proposed clamping gadget and the proposed shoe and to illustrate the related design example the following figures are intended; these are showing.